1. Technical Field
The present invention relates to metal structures for use with integrated circuit devices and other applications, and more particularly to metal spheres and hemispheres and methods for fabrication.
2. Description of the Related Art
Nanorods or nanowires may be formed from the top down or from the bottom up on a substrate. In one method, vertical nanowires are formed from the bottom up using gold nanodots as seeds. The seeds are employed as deposition sites where a high temperature chemical vapor deposition (CVD) process is required to grow the vertical wires from the seeds. This process is difficult to control and undesirable densities and sizes may result. This process is also expensive.
In a top down approach, SiO2 or polymer nanospheres are employed as a mask on a substrate. A solution-based coating process is required which is cost-additive and tends to be non-uniform. The process is characterized by relatively low selectivity etching between the mask and the nanowire materials (substrate). This process is also relatively expensive. In both processes, the temperatures are relatively elevated. This has a detrimental effect on the vertical wires formed.